Is there really any life 'out there'?

Mar 12, 2013

Mankind should not assume that it will definitely find life on alien planets according to a hypothesis being presented at the Royal Society, the UK's national academy of science, this week. Professor Charles Cockell, Director of the UK Centre for Astrobiology at the University of Edinburgh, will raise the possibility that there is no life 'out there' at a discussion meeting entitled Characterising exoplanets: detection, formation, interiors, atmospheres and habitability.

As scientists add to the growing list of planets in the universe which are classed as habitable, Professor Cockell poses an important question – Does life always arise whenever a planet's conditions deem it possible?

On Earth, vacant habitats are rare; most environments that are able to support life do. Professor Cockell argues that this knowledge could be giving us a biased approach to the search for life on other planets.

"The pervasive nature of life on Earth is leading us to make this assumption," said Professor Cockell. "On our planet, carbon leaches into most habitat space and provides energy for microorganisms to live – there are only a few vacant habitats that may persist for any length of time on Earth, but we cannot assume that this is the case on other planets"

Habitable planets may turn out to be abundant in the universe; however the search for life on them may yield many negative results.

"It is dangerous to assume life is common across the universe – it encourages people to think that not finding signs of life is a "failure" when in fact it would tell us a lot about the origins of life," added Professor Cockell.

In his talk, Professor Cockell suggests that scientists should use his hypothesis to avoid the assumption that habitable conditions are likely to contain life, and as a result, approach the question in a more scientifically robust and experimentally testable way.

He also highlights another common assumption that we make when considering extraterrestrial life. That is that life will always result in a signature that we will be able to recognise and detect.

Professor Cockell explains that in coming decades, increasingly powerful telescopes and developments in spectroscopy may allow us to look for the signals of life on planets beyond our solar system. However, regardless of this, our view is still going to be heavily influenced by our knowledge of life on Earth.

In order to detect life on another planet we would need to assume that:

- Once life originates it will usually evolve metabolisms that produce signature gases that we associated with known life.

- Once these metabolisms evolve, the organisms that contain them will usually colonise a planet in high numbers.

- Once the organisms colonise the planet they will usually produce enough gas or surface biosignatures to accumulate at concentrations detectable by us.

Therefore we need to accept the possibility that life could exist on a habitable planet without presenting any signatures that we would recognise as life or be able to detect from Earth.

Researchers attending the Royal Society meeting aim to set the agenda for the next decade in this rapidly expanding field of extra-solar planet science. Some 800 planets orbiting stars outside of our solar system have now been detected, with varying masses and orbital parameters. The challenge now is to move from detection to understanding these planets as bodies in their own right.

Last year came to an exciting end with the discovery of an Earth-like planet, Kepler-22b, orbiting a sun-like star outside of our solar system. It was found by NASAs Kepler mission and is the first planet ...

(Phys.org)—Astronomers find planets in strange places and wonder if they might support life. One such place would be in orbit around a white or brown dwarf. While neither is a star like the sun, both glow and so could be ...

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John Barrow and Frank Tipler have already covered this ground. "Final anthropic principle (FAP): Intelligent information-processing must come into existence in the Universe, and, once it comes into existence, it will never die out." Martin Gardner called it CRAP in the prestigious peer reviewed New York Review of Books.

A 400 amp DC rated power supply was being installed when the technician shut the incorrect breaker. The meter sized ball of ionized stuff, copper from the T-100 cable laying shorted on the floor, slowly floated up out of the pit into the machinery hall. It lasted long enough for me to climb the ladder and watch the crews digging holes in the deck, perhaps 30 seconds.

I still don't see any logical reason, how the isotropic universe excludes the possibility of extraterrestrial civilization. Dare you explain it for us after reading of your source? If not, why we should read it after you?

The fundamentals of physics are isotropic across the observable universe for observable time, putting limits on how different ET can be from us. Not so different that light speed is not a limitation, for instance.

Why should ET choose to visit us? Do you play the lottery with its 1/200,000,000 odds? The chances of ET visiting one of 10E40 stars (Dirac LNH) are worse.

The observable universe is not 10E40 seconds old, disallowing even one star visit per second.

The way I look at it, our little corner of the universe is subject to the same laws of physics as any other. Since the laws of physics were able to assemble self replicating, energy processing units (life) on Earth shortly after it formed, applying the cosmological principle, I see no reason to think why this type of process wouldn't occur elsewhere, and often.

Our ability to detect life, any life, at lightyear distances is both poor and would be open to interpretation (just look at the 'debate' over the Viking lander result).

Some might argue that you need to be a little crazy to ride a Saturn V rocket into space and then go on to visit the moon. But these guys all passed psych tests (as if that's any vindication) so they are (maybe) sane after all. Take astronaut Edgar D. Mitchell, lunar module pilot on the Apollo 14 mission. He holds the record for the longest ever moon walk, at nine hours and 17 minutes along with Alan Sheppard, who was with him at the time. This comes from reputable sources like the Telegraph, from Australia, which reports that "he says extra-terrestrials have visited Earth on several occasions - but the alien contact has been repeatedly covered up by governments for six decades." He should know, because we can assume that he has privileged information, being who he is and doing what he did and everything. And then of course there's Bob Lazar. And Phillip Schneider, who shot 2 aliens while working in a secret underground government base. He's dead. Some say he was murdered. Why?

We've definitely found life right here, and we are on just another world whizzing around a star tucked away in some nondescript region in the galaxy. I don't know why the possibility of life elsewhere is even up for discussion. If we're so doggone important and alone amongst all these countless galaxies then how come we're not in the middle of the Universe? Huh? Tell me that. Is God ashamed of us that he should hide us away like this? AND FROM WHOM? Naw, all the naysayers lose this argument, that's for sure.

So "Intelligent" life on earth proceeds from present to wipe out all competing life forms, then convert its brains into electronic processors needing very little power provided by direct capture and conversion of radiation from its star. Detectable at any distance?

Since the laws of physics were able to assemble self replicating, energy processing units (life) on Earth shortly after it formed, applying the cosmological principle, I see no reason to think why this type of process wouldn't occur elsewhere, and often. - e

Because information does not have evolution. You need information to evolve.

What are you going do to evolve? Horde information? Make information pay tribute to physical law?Locally or globally?Bend and twist information to 'observe'?Make life and death according to physical law and cosmological principles with information?Become God with information?

No they don't because of the 'U' - even by those who have claimed to have seen them.

Making a definite (or even a probability) announcement from something totally unknown isn't scientific. Similarly it isn't scientific to make any claims about what the chances look like that there is any life out there or not.We have no observed life out there and we have't really looked anywhere. The only logically supportable answer right now is: We don't know.

We have one data point about life (ourselves) in the universe. So we know that life isn't impossible. That's it.But you cannot extrapolate anything more from one data point

In B. Mandelbrot's fractally complex reality, and in Andreas Albrecht's QM statistical universe, one myst be vewwy vewwy careful employing inductive inference at all. Connecting the dots, points on an epistemological map is little more than throwing darts in a darkening reality.

Information theory explains all the information you discuss.Now you are discussing the remnant information from that.Information does not have evolution.Answering the metaphysical as well as the physical.I expect no one to see this. Why?You do not see a point in a theory that explains everything.You are not ready nor willing.Instead you ask what amount information represents 'life', 'intelligence' and all other ill-defines of any language.

Just find it within your capacity to forgive the wrong word, at the wrong time, at the wrong place. I see this. You do too.

You can not create 'new' information. Information does not undergo evolution. Whatever magnitude of information content is needed information provides. That is an absolute. You can not 'run out' of information.

The rest of all the other sciences supplies the rest - "the anything sensible or not."

I don't expect anyone to see this. Still, leaving incredulity aside, there is no disagreement between AP and I.Unless AP also rejects the concessional word error and correction just made.

"The magnitude of information content" provided explains why all other sciences will never come up 'short' on information content to support any physical or metaphysical theory.Information does not undergo evolution. Dynamics for the transfer and/or transmission of any information is provided by all the other sciences.

I don't expect anyone to see this. Still, leaving incredulity aside, there is no disagreement between AP and I.

I don't know if there is a disagreement, since you use words and sentence structures like no person I have ever seen before

Seriously: what you write is only really understandeable to one person on the planet: you. All I can evr get from your posts is: you use english words. But what you are actually trying to say with your posts is a complete mystery (in information theory terms: the information content of your posts is zero). To me your usual posts make about as much sense as if you wrote: "Correct baby plumpudding have retracted my sugar not?"

At first I thought you posted while high. But no one can be as consistently on drugs for such a long time. So the current theory is: you're not the sharpest tool in the shed.

The eventual outcome of Mars exploration may be informative on this topic. It looks like Curiosity has sealed the deal on whether Mars was ever habitable, at least for a short time. If it is found that Mars was actually habitable for a very long time, but there is no evidence of life there, then that radically changes the likelyhood of finding life on any given habitable planet.

Usually, the more likely or the more simple an explanation is, the more realistic or the more true it turns out. Obviously, we live in an universe with life, not in one without. How likely is it then, that our universes conditions are such, that during its lifetime life emerges and evolves just once, on one planet, in one solar system, in one galaxy .... ?

How likely is it then, that our universes conditions are such, that during its lifetime life emerges and evolves just once, on one planet, in one solar system, in one galaxy .... ?

If you know anything about stochastics then you know you can't make any calculation based on this (other than saying: the probability of life in this universe is greater than zero.)

It's like someone handing you a ticket that says you have won a lottery. But you don't know how many people played (or what the odds were). All you can say: "Yes: there was a lottery", and "Yes: it was winnable".

So Cockell's hypothesis it is a double whammy of bayesian 'conditions', both for existence and for observability.

But the speed with which life arose on Earth tells us it was easy and/or a frequently occuring chemical evolution attempt 8as event already noted), so is presumably frequent elsewhere. And we have many gases and colorization changes to look at, all outcomes of basic metabolism and cellular growth.

This is not a problem. The problem comes if we want to see intelligent life, because many of _those_ pathways will be unobservable.

@AP: "We have one data point about life (ourselves) in the universe. So we know that life isn't impossible. That's it. But you cannot extrapolate anything more from one data point"

Anyone who has studied stochastic processes know that isn't factual. You can test such models on single data points, lousy estimates as they are. Sometimes in production facilities that is all that you get, still the answer is useful.

This is analogous to how you can test both the existence and the many decades longevity of humans by making a phone call and ask for the respondents age. You would be unlucky to get the answer wrong outside of an order of magnitude by having a child answer.

@Doug: B&T haven't covered anything, because those ideas are not accepted.

And statistical rarities as Monod's "chance" (your "impossibility") are not mapable to dynamics of physical systems. In real systems, with chemical evolution say, likelihoods of outcomes aren't as extreme. (In phase space term, the volume for success in Monod's terms is vanishingly small. Real dynamics have hefty volumes of every possible outcome.)

Sometimes in production facilities that is all that you get, still the answer is useful.

That's not an apt comparison since in production facilities you have a good idea of the processes involved - and therefore can estimate probabilities of things happening again.

For the origins of life we have a lot of unknowns (does gravity play a role? UV light? Is pH critical? Are the currently observed elements the only ones possible? ... )

Until we can create life (or significant precursor analogs on the order of functional RNA in the lab under conditions as might have existed on primordial Earth) we're still very much in the dark about extraterrestrial life.

You would be unlucky to get the answer wrong outside of an order of magnitude by having a child answer

Again you have preknoeldeg here because you already know the possible range in advance. With life in the universe we don't. It's like rolling a die and not knowing how many sides it has. How likely was the 6 you rolled?

So by what I see here, going by the current best estimate of the age of our local universe, we are an extremely crude and very young civilization using what little we know about our own existence as baseline data in the search for extra-terrestrial life in a universe where we have existed for what amounts to the blink of an eye, comparatively-speaking ?

That's not the issue. Once life gets started it grows, changes, diversifies - there's not much question about that. The point here is: How likely is it that it gets STARTED? That is an entirely diffrent question - and one to which we have aboslutely no clue.

The size of the universe gives it a big playing field. But if the chance of life getting started is very small then even in a very big playing field the expected number of occurences can be low.

To reiterate: We just don't know at this point - and we don't have any reliable data to base a guess on.

When teaching YG the art of creating universes, I usually do it in 3 levels, each vastly increasing complexity.

First I let them create Initial Conditions for Standard Universes (ICSU) – similar to the one we all know, with solar systems, galaxies and everything - but where the emergence of live and intelligence is not required.

In level 2, they are to define ICSUs, evolving life and intelligence. Luckily, many YG succeed.

In the Master level - where I'm still stuck too - we aim for ICSUs making sure life emerges only once:1. You need to find ICSUs a) preventing spreading of life within solars systems and b) within and between galaxies and c) allowing life supporting conditions to exist long enough, for life to evolve at least to a stage of crude intelligence (the capability to make powerful bombs, develop rudimentary ethics etc.)

Part II2. If you design ICSUs to make a universe life aware and changing it's conditions itself, once life evolved, how do you make sure that it does not so again in other parts of the universe, before the information to change it's conditions can reach it without breaking the speed of light.

3. A first evolved life and intelligence might develop technology to create and promote life and intelligence itself, overcoming your initial build in conditions.

Needles to say, no one in my classes and non of my peers ever succeeded - not as far as we know, not in a reproduce-able manner, not without interfering after the birth of the universe. Tampering after the birth is regarded as highly unethical, you would lose your status, be kicked out of our gild.

In the Master level - where I'm still stuck too - we aim for ICSUs making sure life emerges only once:

That's not too hard. First you define the conditions for a universe which is closed and has a big crunch. That constrains the values of Omega_matter and Omega_Lambda resulting in a finite universe which will last for a finite time. Then you set remaining constants to make sure that the probability of life emerging on any one planet is roughly than the inverse of the (finite) number of habitable planets that will ever exist in that universe and have an adequate lifetime. You have a good chance that only one will appear though some such universes will have none and some might have two, just discard those and repeat the recipe until you succeed.

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